Erection method for a vaulted membrane structure

Abstract

A tent-like structure, hereinafter called a vaulted membrane structure that has a series of curved arches and a panel of flexible covering material attached to and tensioned between each pair of arches. In one embodiment, the arches on each side of an intermediate portion of the pavilion are mounted to swing in opposite directions between upright and recumbent positions. The arches, except the outermost, are mounted to swing on offsets which increase in length toward an intermediate portion of the pavilion to facilitate attaching of the covering material to the arches and to tension the covering material. The covering material between each pair of arches is depressed to minimize flutter and vibration and to enhance its load-carrying capacity and is attached to the arches by inserting beads on its edges into tunnels in or attached to the arches and held therein by a locking strip. In another embodiment, the arches are movable toward and away from each other to attach the covering material to the arches and to tension the membrane. The structure may be made of curvilinear, circular or ellipsiodal form as well as straight.

I claim: 
     
       1. A method of constructing a vaulted membrane shelter, said vaulted membrane shelter having a structural frame comprised of a multiplicity of substantially vertical arches with curved bights, spaced apart in parallel relationship with their respective ends and apexes aligned, operatively mounted on a base to permit horizontal separating movement; a flexible roof membrane extending between and operatively attached to said arches and said base that is tensioned to a stiffened and substantially wrinkle-free state with an inward concave curvature between the bights of said arches which has a circumferential length in a vertical plane midway between said arches, that is at least 4% less than its circumferential length where it is operatively attached to adjacent vertical arches; means to fix said vertical arches in their erected position to maintain tension in said roof membrane, said method comprising the following steps: a. assembling and disposing said arches on the base in recumbent positions with their corresponding ends aligned in their erected relationship, their crowns similarly oriented but spaced apart to facilitate attachment of said membrane,   b. prefabricating said membrane such that its circumference, in a vertical plane midway between said arches, is less than its circumference where it is operatively attached to said adjacent vertical arches,   c. operatively attaching said roof membrane to at least a portion of the crown of said arches,   d. raising the end arch, that swings away from the remaining arches, to an upright position which, in turn, partially raises at least one adjacent arch,   e. raising the opposite end arch of the shelter, or a section thereof, to an upright position,   f. moving said arches apart to their approximate erected position,   g. tensioning said roof membrane,   h. fixing said arches in space,   i. securing the lower portion of said membrane between the arches.   
     
     
       2. The method described in claim 1 wherein the steps (d) and (e) are being performed substantially simultaneously. 
     
     
       3. The method described in claim 2 wherein the steps (d) and (e) are performed in successive smaller intermediate steps. 
     
     
       4. The method described in claim 1 step (g) wherein the tensioning of said roof membrane includes the elongation of at least one extensible purlin. 
     
     
       5. The method described in claim 1 step (g) wherein the tensioning of said roof membrane includes increasing the tension stress in at least one tension member that extends between an end vertical arch and said base. 
     
     
       6. The method described in claim 5 wherein the tensioning of said roof membrane includes increasing the tension stress in at least one tension member that extends between an end vertical arch and a tensioning means operatively attached to said base. 
     
     
       7. The method described in claim 1 wherein the tensioning of said roof membrane in step (g) includes the movement of end closure arches, operatively attached to said roof membrane, away from the center of said shelter. 
     
     
       8. The method of erection of the shelter described in claim 1 wherein the shelter comprises an end closure that includes an arch inclined outward from the body of the shelter, with its ends attached to said base adjacent to the respective ends of an end arch; a closure membrane extending between, and operatively attached to, said end arch and said inclined arch, and also between said inclined arch and said base, said method further comprising tensioning said closure membrane when performing step (g). 
     
     
       9. The method of erection of the shelter described in claim 1 wherein said shelter includes an end closure that comprises at least one semi-arch having one end attached to the crown of one vertical end arch, and the other end operatively attached to said base, said method further comprising moving outwardly said semi-arch away from the center of the shelter in step (g) to tension said roof membrane. 
     
     
       10. The method of erection of the shelter described in claim 1 except that said shelter is comprised of a multiplicity of substantially vertical arches with their apexes aligned but in non-parallel relationship. 
     
     
       11. The method of erection of the shelter described in claim 1 except that said shelter is comprised of a multiplicity of substantially vertical arches with their apexes non-aligned and spaced in a non-parallel relationship. 
     
     
       12. The method of erection of the shelter described in claim 1 wherein said structural frame of said shelter includes at least one extensible purlin attached to, and extending between said vertical arches. 
     
     
       13. The method of erection of the shelter described in claim 12 except that said roof membrane is operatively attached to said vertical arches after step (e) and before step (f).